He was booked into jail in downtown Los Angeles and is being held without bail.

Two sheriff's officials who had been briefed on the arrest told The Times that a judge asked the rehab facility to notify authorities if Brown showed up.

The facility called authorities Friday when Brown arrived and advised them the singer was supposed to be arrested. After confirming the warrant with the Probation Department, sheriff's deputies arrested the singer.

Several sources said they did not know how Brown may have violated the terms of his probation.

Probation Deputy Chief Reaver Bingham confirmed that his department submitted a report with the court about an alleged probation violation, but he declined to provide details.

He said the “court has to evaluate and consider” the report.

Brown’s attorney, Mark Geragos, said Friday afternoon he didn’t have an immediate comment on the arrest.

In November, the singer was ordered to a 90-day live-in anger-management treatment program, where he would have to complete three eight-hour days of community service each week and undergo periodic drug tests.

Prosecutors in February asked a judge to take Brown into custody for failing to live up to a probation requirement that he "obey all laws."

He was arrested in October in Washington, where he faces a misdemeanor assault charge. He was accused of hitting a man trying to take a picture of him outside the W Hotel.

But Judge James R. Brandlin said he would not jail the singer because he had showed progress in rehab.